Yes, it really is but only for some. I don't exactly know what it would take to qualify but if you use assistive technologies(?) the upgrade is still available.
https://www.microsoft.com/en-us/accessi ... s10upgradeSince I've already upgraded my systems I can't really test this but it seems totally animated. You download a ~6 MB file that takes over.
Personally I think this is a ploy by Microsoft to totally extend the free upgrade without admitting that they failed in their goal as to the number of systems upgraded by 7/29/16. Since there is no way to actually determine if you use assistive technologies anyone could use this method.